Physics

Andalusite Definition Andalusite is a hard, grayish white to pinkish brown orthorhombic mineral. It occurs as nearly square prisms, often with cross-shaped cross sections, in…

Thorite Definition Thorite is a yellow, brownish, or black radioactive mineral consisting of tetragonal thorium silicate. It occurs in coarse granite and is a source…

Zircon Definition Zircon is a brown, reddish to bluish, gray, green, or colorless tetragonal mineral that occurs in igneous, metamorphic, and sedimentary rocks, and especially…

Grossular Definition Grossular is the calcium aluminum garnet and forms in contact or regional metamorphic environments as does andradite the calcium iron garnet. It is…

Almandine Definition Almandine is a deep violet-red garnet that consists of iron aluminium silicate and is used as a gemstone. It is known as a…

Pyrope Definition Pyrope is a deep yellowish-red garnet that consists of magnesium aluminium silicate and is used as a gemstone. It is a member of…

Forsterite Definition Forsterite is any of a group of magnesium iron silicates, (Mg,Fe)2SiO4, occurring in olive-green to gray-green masses as an important constituent of basic…

Phenakite Definition Phenakite is a colourless or white glassy mineral consisting of beryllium silicate in hexagonal crystalline form: occurs in veins in granite with formula:…

Phonon Definition Phonon is a quantized sound wave – a collective vibrational mode of a solid (or liquid). It is the quantum of acoustic or…

Cristobalite Definition Cristobalite is chemically identical to quartz, with the chemical formula SiO2, but has a different crystal structure. Crystals are always microscopic, and usually…

Polymorphism Definition Polymorphism in materials science is refers to the ability of a solid material to exist in more than one form or crystal structure.…

Phosphorus Pentoxide Definition Phosphorus pentoxide is a white odourless solid produced when phosphorus burns: has a strong affinity for water with which it forms phosphoric…